Telegraph-switchboard.



Patented Aug. |5,'|899.

J. F. SKIRROW.

TELEGRAPH SWITCHBOAHD.

(Application led Apr. 11, 1899.)

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UNITED STATES PATENT OFFICE.

JOHN E. sKIRRoW, OE EAST ORANGE, NEW JERSEY.

TELEG RAPH-SVi/ITCHBOARD.

SPECIFICATION forming part of Letters Patent N0. 631,132, dated August 15, 1899.

Application filed April 11, 1899.

To all whom it may concern.:

Beit known that I, JOHN F. SKIEEOW, a citizen of the United States, residing at East Orange, in the county of Essex, State of New Jersey, have made certain new and useful Improvements in Telegraph-Switchboards, of which the following is a specification.

My invention is an improvement in the apparatus for connecting main lines with loop or branch lines and With office instruments.

The objects of my invention are to simplify and reduce the number of flexible cords in use, to avoid the use of permanently-attached cords, to render any loop or office instrument available for use at anyone of anumber of switchboards, and to provide a cord to be employed above the tableV and which may be' lengthened or shortened without the use of either a gravity or spring take-up device.

I provide one or more vertical switchboards with horizontal working tables, each vertical board having preferably a series of notched straps with a series of intermediate electrically-connected rows of notched disks to receive the connecting-pins. The circuits connected to the vertical straps in these boards terminate in or include any Well-known form of spring-jack. The horizontal tables have a series of springjacks, preferably of the metallic-circuit type. Corresponding jacks of this series on each board are connectedto wires, which in turn are electrically connected with a table set of instruments or with a loop extending to a branch oli'ice or a circuit extendingto anylocaloficeorconnection. This Y renders any such instrument or loop available at any board without the employment of the usual arrangement of transfer-connections employing numerous ixed flexible cords.

Any Wire or circuit on a vertical board may be connected to any loop or instrument by employing a flexible cord With suitable terminals or. double contact connecting pins. For this purpose I'provide cords which are located in full View above thehorizontalboard. Each cord is susceptible of being removed, replaced, lengthened, or shortened. This adjustability is attained by placing upon the cord sliding mechanical connections with a ring or eye through which the cord is looped or arranged in convolutions. Then by causing the sliding connections to approach and Serial No. 712,600. (No model.)

recede With respect to each other, the convo' lutions may be shortened orlengthened, and the extent of separation between the cord-terminals or pins is extended or contracted to suit the requirements of any particular case.

The accompanying drawings illustrate my invention.

Figure 1 is a complete diagrammatic view of the arrangement of two switchboards with means for connecting any main circuit with any loop or desk set. Fig. 2 is a view of the improved arrangement of conducting-cord. Fig. 3 is a detail view of the mechanical connecting device on the cord'.

S and S are Vertical switchboards having horizontal tables H. Each switchboard has a series of vertical strips s, to which the main circuits are connected. Each horizontal row of metal buttons b is'electrically united by a Wire or strip soldered or screwed to each but; ton. This is located ou the rear side of the board in the usual and well-known manner. There are arc-shaped notches n in the but tons b and in the strips s to receive suitable connecting-pins. Each vertical strips is connected to theground throu ghl the spring-jack J in a well-known manner. The horizontal tables l-I are each equipped with a series of small spring-jacks j, and corresponding jacks j on each table are connected with the same conductors. Pairs of conductors, like 13 14 15 16, are provided, and these extend to each one of a series of boards. Each such pair of conductors forms the terminals, respectively, of either a setof desk instruments or a loop extending to a branch oce in which is located a set of instruments, the object being to provide for looping any branch oflice or any desk set of instruments into any mainline circuit either of the ground-return or metallic circuit type. The first spring-jacks j at the left on each table are connected With the conductors 13 14, extending from one board to the other. The second spring-jacks j on each table are connected with the conductors 15 and 16 of the same extent.

D is a desk set of Morse instruments permanently connected with the conductors 15 and 16 by the wires 5 and 6. v

A is a branch station connected by a loop 3 4 with the conductors 13 and 14.

By the use of flexible cords, like C, located IOO Y above the horizontal tables H, any vertical strip s and its main conductor or circuit may be connected with any loop or desk set, like A or D. This is done by inserting the plug I in a spring-jack .I and the pin p in the proper spring-jack j. It is to be understood that the jack j may be of either the double or metallic circuit or the single or groundreturn circuit type. I have shown them of the double conductor metallic circuit arrangement With cord-terminals or pins to correspond.

Vhere the cords are located above the table H, it is desirable to minimize the space occupied by such connecting devices, and as these cords are transferable or movable, as distinguished from being permanently attached, it is desirable to limit the space occupied by each. The maximum number of such cords required is the greatest number in use at any one time. Heretofore it has been necessary to employ a special conducting-cord fixed at one end.

I employ a special improved form of conducting-cord C. This is equipped with plugs or tips P and p, suitable for use with the jacks J and j, respectively. Each cord is arranged in convolutions passing through suitable sliding mechanical connecting devices. These mechanical connecting devices consist of a cylinder or tube section T, arranged to slide easily upon the exterior of the conductor C, which is preferably a stranded conductor covered with silk insulation, but may be of any suitable character. Forming part of each mechanical connecting device is an eye or ring t'. There are two of these connecting devices T, normally located on the cord near the base of the tips thereof. The cord is fixed at each end of its tip or plug. Tracing the course of the cord from either tip, it passes through the nearer mechanical connecting device T, thence to the eye or ring t' of the opposite connecting device, thence back to the eye or ring of the device first named, thence through the second connecting device T. By taking the tips of the cord one in each hand and pulling in opposite directions the cord is lengthened, the convolutions shortening, and the mechanical connecting devices T moving toward each other as the convolutions contract. By taking the two mechanical connecting devices T one in each hand and pulling them in opposite directions the convolutions of the cord are lengthened and the tips of the cord are caused to approach each other till the minimum extent is reached.

What I claim, and desire to secure by Letters Patent, is

1. A flexible connecting-cord for uniting electric circuits consisting of an insulated conductor, two sliding sleeves located thereon, a ring or eye on each sleeve through which the cord passes and suitable terminals or pins for each end of the cord'substantallyas described.

2. A flexible insulated conductor having a suitable pin or terminal at each end and means foradj ustin g the length of said conductor consisting of two metal sleeves sliding upon the surface of the conductor, and a ring or eye upon each sleeve through which the cond nctor is passed substantially as described.

JOHN F. SKIRROW. Witnesses:

M. S. BIRD, THEonoRE L. CUYLER, Jr. 

